Effect of Hybrid Fibers on Water absorption and Mechanical Strengths of Geopolymer Concrete based on Blast Furnace Slag

In recent years, geopolymers, as a new class of green cement binders, have gained significant attention as an environmental-friendly alternative to Ordinary Portland Cement (OPC) which can potentially reduce negative environmental impacts of OPC. Fiber Reinforced Geopolymer Concrete (FRGPC) is known as a new type of concrete with enhanced ductility characteristics over conventional concrete. In this experimental study, hybrid fibers of 12mm modified polypropylene and 55mm polyolefin were used to manufacture FRGPC specimens based on Granulated Ground Blast Furnace Slag (GGBFS). In this regard, FRGPC and non-fiber specimens were produced. The specimens were subjected to compressive, indirect tensile and 3-point flexural tests, as well as water absorption capacity and specific density studies. The obtained results showed that using hybrid fibers decreased the specific density and water absorption, a slight increase in compressive strength and a significant improvement in tensile and flexural strengths of FRGPC specimens compared to non-fiber specimens.